Elephant Fluid Power Co., Ltd.
Elephant Fluid Power Co., Ltd.

What Are the Characteristics and Functions of Directional Control Valves?

The directional control valve is mainly used to open and close the oil circuit or switch the direction of the oil flow to meet the requirements for the start, stop and movement direction of the actuator. According to its use, it can be divided into two categories: one-way valve and directional control valve.


Ⅰ. The characteristics of the directional control valve


1. In petroleum, chemical, mining and metallurgy industries, directional control valve is an important fluid reversing equipment. The valve is installed in the pipeline that delivers lubricating oil in the thin oil lubrication system. By changing the relative position of the sealing component in the valve body, each channel of the valve body is connected or disconnected, so as to control the reversal and start and stop of the fluid.


2. In the powder conveying industry and the environment of the pneumatic conveying system, the directional control valve is an important powder reversing equipment. It is installed in the conveying pipeline and adjusts the shaft baffle by pneumatic control to change the direction of the material in the channel.


3. The directional control valve has accurate action, high degree of automation, stable and reliable work, but needs to be equipped with a driving and cooling system, and the structure is more complicated; the valve disc structure is relatively simple, and is mostly used in production processes with small flow.


Ⅱ. The role of the directional control valve


The function of the directional control valve is to use the movement of the spool position to change the on and off state of each oil port on the valve body, thereby controlling the connection, disconnection and direction change of the oil circuit. The directional control valve is a valve that uses the change of the relative position of the valve core and the liquid to change the communication relationship between the valve ports, thereby opening and closing the liquid passage, controlling the flow direction of the liquid, and controlling the start, stop and movement direction of the actuator. Working reliability refers to whether the electromagnet can reliably change direction after power-on, and whether it can be reset reliably after power-off. Solenoid valves can only work normally within a certain flow and pressure range. The limit of this operating range is called the commutation limit.


Internal leakage: Under different working positions and specified working pressures, the leakage from the high pressure chamber to the low pressure chamber is internal leakage. Excessive internal leakage can not only reduce the efficiency of the system and cause overheating, it can also affect the proper operation of the actuator.


The commutation frequency is the number of commutations allowed by the valve per unit time. At present, the commutation frequency of single solenoid solenoid valve is generally 60 times/min. Service life, the service life of the solenoid valve mainly depends on the electromagnet. Wet electromagnets have a longer lifespan than dry electromagnets, and DC electromagnets have a longer lifespan than AC electromagnets.